Turn Opus files into AIFF
This makes an AIFF out of the Opus you already have. Opus gives you the best sound for the size of any common audio format, and handles speech and music equally well. Worth knowing: an AIFF will not open in a browser tab, so it is a file for software rather than for the web. Your file never leaves your computer.
Need the other direction? Convert AIFF to Opus
How to convert Opus to AIFF
- 1 Drop your Opus .opus file onto the page, or click to browse for it.
- 2 Check the options. Nothing is thrown away on the way to AIFF, so there is no quality dial to set.
- 3 Convert. The work happens on your own machine, so how long it takes depends on your computer and the file.
- 4 Download the AIFF, or add more files and do the whole set in one go.
Why convert Opus to AIFF
- You want a copy that will not get any worse each time you edit and save it, and AIFF gives you that.
- Exactly as recorded, identical in quality to a WAV.
- Holds track details better than a plain WAV.
- Professional recording and mastering on macOS.
- Opus: fewer editing tools handle it directly.
Opus compared with AIFF
How the two formats differ on the things that decide whether a conversion is worth making.
| Property | Opus | AIFF |
|---|---|---|
| File extension | .opus | .aiff |
| Compression | Lossy | Uncompressed |
| Typical file size | Smaller | Largest |
| Browser support | All current browsers | Some browsers |
| Introduced | 2012 | 1988 |
| Developed by | Xiph.Org and IETF | Apple |
Quality and what changes
AIFF stores every pixel exactly, but it can only preserve what the Opus already contained. The compression artefacts baked into the source are preserved perfectly along with everything else, so the picture does not improve, it just stops degrading. Expect the file to grow substantially, often several times over, because Opus was discarding data that AIFF now has to write out in full.
- Browsers will not display an AIFF, so it downloads rather than opening in a tab.
- One AIFF limitation to keep in mind: less universally supported on Windows and web.
Questions about Opus to AIFF
Does converting Opus to AIFF improve the quality?
No. AIFF preserves what it is given perfectly, including the compression artefacts already present in the Opus. It stops further loss from happening, which is worth doing before editing, but it cannot recover detail that was discarded.
Why is my AIFF bigger than the Opus?
Because Opus was discarding data and AIFF is not. A lossless format has to write out every pixel it is handed, artefacts included, so growing several times over is normal and does not mean anything went wrong.
Is my Opus file uploaded anywhere?
No. The whole thing runs inside the browser tab you already have open. Your Opus is read straight from your own disk, converted on your machine and handed back as an AIFF. Nothing is sent anywhere, nothing is stored and there is no account.
Is there a file size limit?
There is no server-side limit because no server sees the file. The real ceiling is your device memory, since the input and the output both have to fit in the tab. A few hundred megabytes is usually fine on a desktop machine and considerably less on a phone.
Can I convert several Opus files at once?
Yes. Add as many as you like and they are processed one after another, then offered as separate AIFF downloads or as a single ZIP. Speed depends on your own processor rather than on a queue.
Does the converter work offline?
Yes, after the page has loaded once. The engine is cached by the browser, so you can disconnect, reload and keep converting. That falls out of doing the work locally rather than being a separate mode you switch on.